Nitrogen-Doped Carbon Encapsulated Partial Zinc Stannate Nanocomposite for High-Performance Energy Storage Materials

As a bimetal oxide, partial zinc stannate (ZnSnO₃) is one of the most promising next-generation lithium anode materials, which has the advantages of low operating voltage, large theoretical capacity (1,317 mA h g^-1), and low cost. However, the shortcomings of large volume expansion and poor electrical conductivity hinder its practical application. The core-shell ZnSnO₃@ nitrogen-doped carbon (ZSO@NC) nanocomposite was successfully obtained by coating ZnSnO₃ with polypyrrole (PPy) through in situ polymerization under ice-bath conditions. Benefiting from this unique compact structure, the shell formed by PPy cannot only effectively alleviate the volume expansion effect of ZnSnO₃ but also enhance the electrical conductivity, thus, greatly improving the lithium storage performance. ZSO@NC can deliver a reversible capacity of 967 mA h g^-1 at 0.1 A g^-1 after 300 cycles and 365 mA h g^-1 at 2 A g^-1 after 1,000 cycles. This work may provide a new avenue for the synthesis of bimetal oxide with a core-shell structure for high-performance energy storage materials.